Illuminating means for motor-heat indicators



Dec. 18, 1928. 1,695,707

H. H. BOYCE ILLUMINATING MEANS FOR MOTOR HEAT INDICATORS Filed Sept. 27, 1923 2 Sheets-Sheet l Z2 4 75 v 1 75' i O I %Lea/ 2 ATTORNEYS Dec. 18, 1928. 1,695,707 H. H. BOYCE ILLUMINATING' MEANS FORMOIOR HEAT INDICATORS Filed Sept. 27, 1923 2 Sheets-Sheet 2 mvamoa zwwzim 7M:-

ATTORNEYS Patented Dec. 18, 19 28.

UN D/ TATE ,PATENT' HARRISON BOYCE, OF ERIoHo, NEW YOR 'ILLUMINATING MEANS For; MOTOR-HEAT INDICATORS.

- Application filed September 27, 1923. Serial No. 665,254.

This invention relates to illuminating devlces, and. more particularly to illuminating devices for. use in illuminating; instruments forindicatingthe thermal conditions of int ernal combustionengines of motor veh cles and the like.

of the car.

The instruments in most general use as.

motor heat indicators 'for automobiles comprise a temperature'responsive lndicatmg de vice-mounted on the radiator cap at the front 7 conditions, however, .itsindications-are in someinstances vdifficult to read at night.

It is an object ofthepresent invention to provide means for illuminating motor heat indicators of the typedescribed, to enable to illustrate.the-invention comprises a motor them to be read at night, whichcan be readily applied to the indicators now in use.

Other jbjects are to provide an illuminating device which can be mounted upon the temperature its ornamental effect, which will {not interfere with the drivers vision of theroadat night and will illuminate theentire india cator and scale toa uniform intensity.

Various other objects and advantages, w11 l appearas the description proceeds.

Referring now 'to'the drawings which illustrate one embodiment of the inventionas applied to a motor heatindicator in common use, Fig.:1 is a front elevationof such an indicator with the device applied thereto.

7 Fig. 2is a longitudinal sectional view of the form of embodiment shown in lilig 1.

V, Fig. 3is a front elevation of. the scale plate showing the groove for the illuminatingde vice therein. r j .1

Fig. 4 is across sectional view theindicator and device looking down inFig. 1.

Fig.5 is a rear view. i

I Fig. 6 is a pa-rtdiagrammatic,view showing the-indicator and illuminating device mounted onthe radiatoraof an internal combustion engine. l f i The embodiment of the instrument chosen heat indicator 30f a well-known. form now in common use, in which 7 the crystal rordinarilyplaced 'at the reariofthe indicator has This location of ,the instrument indicatorw without substantially changing its appearance or decreaslng been removedeand replaced by the disc 15 illumiwhich, serves as a housing for the natlng device to be described. V

The llumlnatingdevlce consists of a closed tube-1, containing a rarefied gas, as for example neon, which is adapted .to glow when 1 subjected to a potential difference of the in I i tensity ordinarily employed for the spark plugs of internal combustion engines; and an, electrode 2 for connectlngthe tube to a suitable source of electrical potential. .This

tube is illustrated as being applied to a mo tor heat indicator 3 of well known form comprising an annular frame 4 with a base5,

adapted to rest upon the top of theradiator cap 6. A suitable project-ion or housing 7 extends from the frame 4 throughthe radiator cap and intothe radiator, and is screw threaded at 8 for the purpose of receiving a nut to hold the frame l uponthe radiator cap.

Extending.

thermometer tube 10, containing an expansible fluid such as alcohol, which constitutes the mdicating element of the instrument. f

from inside the projectiony'i into the opening 9 in the frame 4 isaglass The front'of the frame 4 isclosedby a transparent crystal 11, the edgesof' which rest upon a suitable packing washer 12,

e5 placed in an annularrecess 12 formed in. the frame, while'the" crystal is held in place by a ring13, which overlaps the edgesof the 7 crystal and is attached to the frame by the screwsll. .7 h r In the instruments of this character now in use'are a'suit'ably marked dial plate placed 15= formedin the back ofthe frame, and be hind the dial plate a name plate bearing ance thereof when viewed from either front or rear. This is accomplished in thefform of the invention illustrated by removing the rear retaining ring and crystal together with the dial plate: and-name plate and substitutring the construction to; be described.

behindthe glass tube 10 in an. annularrecess In applying the illuminating means to an sulating material 15, which; maybe, bakelite or the like. This disc is of sufiicient thickness to encloseor housethe illuminating tube 1, and is provided for that purpose with a receptacle in the form ofavertical groove 16, a hollow extension 17 being provided to permit the electrode 2 to beinserted into the frame and to insulate it from the same.

The top of the tube 1 is held'in place; by a packing washer 12 inserted between the r 1 rear of the frame 4 andthe disc15, and by suitable packing'inthe top ofthe groove 16, and the bottom rests upon a suitable packing and conductive material 18, as for example, steel wool, so as to prevent breaking of the tube 1' due to the vibrations of the temperature indicator and so as to produce the desired electrical excitation ofthe gas within the tube. In addition to housing the illuminator tube 1, the disc 15 may have inscribed upon its face suitable letters 19 and designs 20, such asill-ustrated in Fig. 3*, so that'the iace ofthe discserves also as a dial or scale, by which the various temperature changes recorded by. the heat indicaton may beread and interpreted.

An opening 21 is provided through the disc 15* so as to renderthe column of fluid in the tube 10 very distinctly visible to the driver whenydue to abnormal temperature conditions the column risesto such a height as to enter thelower limits of the opening: 21".

The rear face of'thedisc 1-5 is covered by a crystal 11" which rests against a packing washer 1 2* and is held in place-by aring- 13 and screws 14 which also pass through the.

holes 22 in the disc 15 andinto theframe 4 to hold thedi'sc and crystal in place.

Ifdesired a nameplate 23 may be insented between the disc 15 and the crystal: 11 and carry a tradeqnarl; or design 24 which is visble from therear ofthe instrument. The nameplate 23? is provided with an openingflfi inyegi'stry with the openingQl inthe disc lh.

In the use of the device the indicating instrument is positioned; on the radiatoaoakpfi,

{ts-illustrated in Fig. 6, and the electrode 2 is connected to a source of'suitahle potential difference, as for example, thespark plug 26, by the conductorQT. A condenser 28 is introduced into the conductor 27' to prevent leakage of" the current and grounding of the plug 26and to permit the use-ofuninsulated conductors in certain instances. W'here a well-insulated conductor is used, the condenser may be omitted; By this arrangement,,the illuminator 1 is caused to glow each time the spark plu subjected toa potential difference for producing a sparkin the cylinder. a

At high speeds, the glowing of the illuminator produces a continuous lightwhich illnminaites'the thermometer tube 1 9 and the scale 19 and 20 so as to enable the same to be easily read from the drivers seat at night, and at. the Lower speeds tha intermittent flashes serve to attract attention to the heat indicator soithmt iifi indicationswillnpt pass unnoticed.

While the invention has been described as applicable to the-heat indicators now in use, it is, of course, obvious that the invention may as readily'be applied toithe heat indicators tobemanufactured in the future In compliance with the patent statutes. a

sp cificembodimentofi' the invention. and

ment comprising; a temperatune indicator, a

ring shaped casing enclosing: said; indicator, and an attachment including anelongated tube containinga rarefied gas adaptedtoglow when subjected to sparkplug potential; a. block, an open groove in the'blockfror pmntiahlyenclosing said: tube, aarear crystaha name lateinterposed between said cnystaliandzsmid lock, and means passing through the block at a. plurality of points for seen-Ding theiblock,

the name plateaamd the erystwl' all! toitherear wall of said casi'plg 2". In a heat in eating meansfiorintennal combustion engines, the combination of:- a

frame adapted to-be secured torthe radiator ca of the-engine, a means in. the frame for in icatih the heat ofi the engine, a crystal overthe %ront oftheirame, a scaleplate at the rear oi? theframeandan illuminating device in the plate, a crystal 'atthe rear ofithe plate and means passingthnough the plate andihtothefhameand holdingboth the crystal and plate in the frame. 7 r

3. In a heat indicatingmeans for internal combustion engines, the combination of a' fi'ame adapted to besecured to. the radiator cap at the engine, means in the firame for indicatingthe heat of the engine, a di'skatthe rear oi? the-frame and filling the same behind the heat indicating means, an open groove-in the disk, anilluminating tube adapted to low when subjected to spark plug potential 1n the groove, means passing through the disk and into the frame to secure the disk in. the frame, and means tosubj ect the, glow: tube to spark plug potentiah 4. In combination, an internalcombustion en i-nehaving a source 05 spark plugpotenti'a the device comprising a tube containing a. heatresponsive element and a frame, a scale 7 plate within the frame behind said; tube, a a

groove in the plate, a tube'adapted to. glow I 1,695,707 "1 Y Y if 3 .Whefi' subjectedto' spark tplugi'r n tefiti ilnamefiilateand the ssh; p ate a l-0n. the I mounted ilnrthe-gtroove behind the tube nd meansoutsid'e thelframfito c011 lar opening near the top of the'plate, aname gine. V

mining the heat responsive element, a circue meet the glow tube to a'sp aafk-plug of the en 1 i0 5 plate behind the scale plate,'aierystal cover In testimony whereof I ha e atfixed my a I ing the name plate, means passing through J signature '09 this specification; the scale plate and" holdingthe crystal, the] I HARRISON HQBQYCEi 

